It is the second of three days of witness testimony and public inquiry by the National Transportation Safety Board into the January midair crash over the Potomac River.

Investigators have found that a helicopter involved in a deadly crash with a passenger plane over Washington was flying above its height limit. The helicopter's altitude-measuring instrument was also inaccurate.

The National Transportation Safety Board will wrap up its public testimony on Friday about the fatal midair crash between an Army helicopter and a commercial jet earlier this year